1. Field of the Invention
The present invention relates to a rack structure, and more particularly to a rack structure for a chair that may maintain the user's correct sitting posture by swing the frame thereof.
2. Description of the Prior Arts
For comfort, most chairs are equipped with a back rack. Therefore the rack structure will be a requirement for a comfortable chair.
A conventional rack structure includes a frame comprised of a back plate (the back plate includes soft materials, such as foam material, filled therein) for providing comfort as a user sits on the chair and lays against its back. However, such a conventional chair can not make the user correct his sitting posture if sitting on the chair in an incorrect manner, causing fatigue.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.